Resectable Esophageal Adenocarcinoma Research Articles

Integrating Clinical Variables, Radiomics, and Tumor-derived Cell-Free DNA for Enhanced Prediction of Resectable Esophageal Adenocarcinoma Outcomes

The value of integrating clinical variables, radiomics, and tumor-derived cell-free DNA (cfDNA) for the prediction of survival and response to chemoradiation of patients with resectable esophageal adenocarcinoma is not yet known. Our aim was to investigate if radiomics and cfDNA metrics combined with clinical variables can improve personalized predictions. A cohort of 111 patients with resectable esophageal adenocarcinoma from 2 centers treated with neoadjuvant chemoradiation therapy was used for exploratory retrospective analyses. Models combining the clinical variables of the SOURCE survival model with radiomic features and cfDNA were built using elastic net regression and internally validated using 5-fold cross-validation. Model performance for overall survival (OS) and time to progression (TTP) were evaluated with the C-index and the area under the curve for pathologic complete response. The best-performing baseline models for OS and TTP were based on the combination of SOURCE-cfDNA that reached a C-index of 0.55 and 0.59 compared with 0.44 to 0.45 with SOURCE alone. The addition of restaging positron emission tomography radiomics to SOURCE was the most promising addition for predicting OS (C-index: 0.65) and TTP (C-index: 0.60). Baseline risk stratification was achieved for OS and TTP by combining SOURCE with radiomics or cfDNA, log-rank P < .01. The best-performing combination model for the prediction of pathologic complete response reached an area under the curve of 0.61 compared with 0.47 with SOURCE variables alone. The addition of radiomics and cfDNA can improve the performance of an established survival model. External validity needs to be further assessed in future studies together with the optimization of radiomic pipelines.

High proportion of PD-1 and CD39 positive CD8+ tissue resident T lymphocytes correlates with better clinical outcome in resected human oesophageal adenocarcinoma

ObjectiveTo understand the CD8+ tumour infiltrating lymphocyte (TIL) compartment of oesophageal adenocarcinoma (OAC) with regards to markers of lymphocyte exhaustion, tissue residency and to identify possible reasons behind differential responses to therapy.DesignTumour samples from 44 patients undergoing curative resection for OAC were assessed by flow cytometry for presence of antigen-experienced TILs and markers of activation and exhaustion. Populations of PD-1 and CD39 positive OAC TILs were sorted, and bulk RNA sequencing undertaken using a modified SmartSeq2 protocol. Flow cytometric assessment of functionality was completed.ResultsA higher proportion of antigen experienced CD8+ OAC TILs was associated with improved survival following surgery; while, high double positivity (DP) for PD-1 and CD39 among these TILs also correlated significantly with outcome. These DP TILs possess a minority population which is positive for the markers of exhaustion TIM3 and LAG3. Transcriptomic assessment of the PD-1 and CD39 DP TILs demonstrated enrichment for a tissue resident memory T lymphocyte (TRM) phenotype associated with improved survival in other cancers, reinforced by positivity for the canonical TRM marker CD103 by flow cytometry. This population demonstrated maintained functional capacity both in their transcriptomic profile, and on flow cytometric assessment, as well as preserved proliferative capacity.ConclusionResected OAC are variably infiltrated by PD-1 and CD39 DP TILs, an abundance of which among lymphocytes is associated with improved survival. This DP population has an increased, but still modest, frequency of TIM3 and LAG3 positivity compared to DN, and is in keeping with a functionally competent TRM phenotype.

281. PROTEOMIC, TRANSCRIPTOMIC AND GENOMIC ANALYSIS OF ESOPHAGEAL ADENOCARCINOMA UNCOVERS CANDIDATE THERAPEUTIC TARGETS AND CANCER-SELECTIVE POST-TRANSCRIPTIONAL REGULATION

Abstract Background Addressing the poor prognosis associated with esophageal adenocarcinoma (EAC) has been hindered by the absence of biomarkers for early disease detection and therapeutic targets. Despite extensive research on the somatic mutations associated with EAC, the impact of genomic aberrations on protein expression and cancer phenotype remains unclear. Methods We conducted a quantitative proteomic analysis using tumour tissue and patient-matched adjacent normal esophageal and gastric tissues from 23 patients undergoing resection for EAC. We further examined the relationship between transcript and protein levels using patient-matched whole transcriptome RNA sequencing and proteomic data from 7 patients and integrated these findings with data from a cohort of 264 EAC patients with RNA sequencing and 454 patients with whole-genome sequencing, as well as external published datasets. Results We quantified protein expression from 5897 genes in EAC and normal tissues. Several potential biomarkers showing selective expression in EAC, such as the transmembrane protein GPA33, were identified. We validated the EAC-specific expression of GPA33 in an external cohort of 115 patients, suggesting its utility as a diagnostic and therapeutic target. Additionally, integrated analysis of protein and RNA expression in EAC and normal tissues revealed genes with discordant protein and RNA levels, indicating post-transcriptional regulation of protein expression. These outlier genes, including SLC25A30, TAOK2, and AGMAT, exhibited rare somatic mutations, suggesting post-transcriptional mechanisms driving this EAC-specific phenotype. AGMAT, as an example, was found to be overexpressed at the protein level in EAC compared to adjacent normal tissues, with a proposed EAC-selective, post-transcriptional mechanism regulating protein abundance. Conclusion Through quantitative proteomic analysis, we identified GPA33 as a candidate EAC biomarker. Integrated analysis of the proteome, transcriptome, and genome in EAC uncovered genes with tumor-selective post-transcriptional regulation of protein expression, offering potential exploitable vulnerabilities for therapeutic intervention.

A comparative assessment of ACS NSQIP-predicted and actual surgical risk outcomes of robotic transhiatal esophagectomy for esophageal adenocarcinoma resection at a high volume institution.

Esophageal adenocarcinoma incidence is increasing in Western nations. There has been a shift toward minimally invasive approaches for transhiatal esophagectomy (THE). This study compares the outcomes of robotic THE for esophageal adenocarcinoma resection at our institution with the predicted metrics from the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP). With Institutional Review Board (IRB) approval, we prospectively followed 83 patients who underwent robotic THE from 2012 to 2023. Predicted outcomes were determined using the ACS NSQIP Surgical Risk Calculator. Our outcomes were compared with these predicted outcomes and with general outcomes for transhiatal esophagectomy reported in ACS NSQIP, which includes a mix of surgical approaches. The median age of patients was 70years, with a body mass index (BMI) of 26.4kg/m2 and a male prevalence of 82%. The median length of stay was 7days. The rates of any complications and in-hospital mortality were 16% and 5%, respectively. Seven patients (8%) were readmitted within a 30-day postoperative window. The median survival is anticipated to surpass 95months. Our outcomes were generally aligned with or surpassed the predicted ACS NSQIP metrics. The extended median survival of over 95months highlights the potential effectiveness of robotic THE in the resection of esophageal adenocarcinoma. Further exploration into its long-term survival benefits and outcomes is warranted, along with studies that provide a more direct comparison between robotic and other surgical approaches.

Prospective randomized multicenter phase III trial comparing perioperative chemotherapy (FLOT protocol) to neoadjuvant chemoradiation (CROSS protocol) in patients with adenocarcinoma of the esophagus (ESOPEC trial).

LBA1 Background: The most effective multimodal approach for treatment of resectable locally advanced esophageal adenocarcinoma (EAC) is under debate. A prior ranking question is if neoadjuvant chemoradiation therapy or perioperative chemotherapy is superior. ESOPEC (NCT02509286) is a multicenter prospective randomized trial comparing neoadjuvant CROSS (41.4Gy plus carboplatin/paclitaxel) followed by surgery versus perioperative FLOT (5-FU/ leucovorin/oxaliplatin/docetaxel) and surgery for the curative treatment of EAC. Methods: Patients with cT1 cN+ cM0 or cT2-4a cNany cM0 resectable EAC were eligible. The primary endpoint is overall survival (OS; 90% power; hazard ratio [HR] 0.645, 218 events needed; one sided significance level of 2.5%). Analysis is by intention-to-treat in all randomized patients. The effect of treatment on OS is estimated using Cox regression stratified by study site, and including N stage (N0, N+), and age as covariates. Results: Between Feb 2016 and Apr 2020, 438 patients from 25 sites in Germany were randomly assigned to two treatment groups (221 FLOT; 217 CROSS). Baseline characteristics (male sex 89.3%, median age 63 [range 30-86], cT3/4 80.5%; cN+ 79.7%) were well balanced between both arms. Neoadjuvant treatment was started in 403 patients (207 FLOT; 196 CROSS). Surgery was done in 371 patients (191 FLOT; 180 CROSS). R0 resection was achieved in 351 patients (180 FLOT; 171 CROSS). 90 days postsurgical mortality was 4.3% (3.2% FLOT; 5.6% CROSS). After a median follow up of 55 months, 218 patients had died (97 FLOT; 121 CROSS). Median OS was 66 (95% CI 36 – not estimable) months in the FLOT arm, and 37 (95% CI 28 – 43) months in the CROSS arm. The 3-year OS rates were 57.4% (95% CI 50.1 – 64.0%) for FLOT and 50.7% (95% CI 43.5 – 57.5%) for CROSS (HR 0.70, 95% CI 0.53-0.92, p=0.012). In 359 patients with available tumor regression status, pathological complete response was achieved in 35 (19.3%, 95%-CI 13.9 – 25.9%) in FLOT and in 24 (13.5%, 95%-CI 8.8 – 19.4%) in CROSS. Conclusions: Perioperative FLOT improves survival in resectable EAC compared to neoadjuvant CROSS. Funding: The trial was funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation), project number 264590883. Clinical trial information: NCT02509286 .

Preoperative docetaxel, cisplatin, and 5-fluorouracil for resectable locally advanced esophageal and esophagogastric junctional adenocarcinoma

BackgroundChemotherapy consisting of 5-fluorouracil, leucovorin, oxaliplatin, and docetaxel is the standard perioperative treatment for resectable esophageal adenocarcinoma and esophagogastric junctional adenocarcinoma (EGJ-AC) in Western countries. Meanwhile, preoperative chemotherapy consisting of docetaxel, cisplatin, and 5-fluorouracil (DCF) has been developed for esophageal squamous cell carcinoma in Japan. However, there are few reports on the safety and efficacy of preoperative DCF for resectable EGJ-AC in the Japanese population.MethodsPatients with histologically confirmed resectable EGJ-AC who received preoperative DCF (docetaxel 70 mg/m2 and cisplatin 70 mg/m2 on day 1 and continuous infusion of 5-fluorouracil 750 mg/m2/day on days 1–5 every 3 weeks with a maximum of three cycles) between January 2015 and April 2020 were retrospectively evaluated. We assessed the rates of completion of ≥ 2 courses of DCF and R0 resection, histopathological response, progression-free survival (PFS), overall survival (OS), and adverse events.ResultsThirty-two patients were included. Median follow-up was 28.7 (range, 5.2–70.8) months and median age was 63 (range, 42–80) years. Twenty-one patients (66%) had a performance status of 0. The proportions of clinical stage IIA/IIB/III/IVA/IVB disease were 3%/0%/44%/44%/9%, respectively. The treatment completion rate was 84%. A histopathological response of grade 1a/1b/2/3 was obtained in 58%/26%/13%/3% of cases. Median PFS was 40.7 months (95% confidence interval 11.8-NA). Median OS was not reached (80.8% at 3 years). Grade ≥ 3 adverse events were observed in 63% of cases (neutropenia, 44%; febrile neutropenia, 13%). No treatment-related deaths occurred.ConclusionsPreoperative DCF for resectable EGJ-AC was well tolerated and has promising efficacy.

Treatment of esophageal adenocarcinoma in patients with a history of bariatric surgery

The relationship among obesity, bariatric surgery, and esophageal adenocarcinoma (EAC) is complex, given that some bariatric procedures are thought to be associated with increased incidence of reflux and Barrett's esophagus. Previous bariatric surgery may complicate the use of the stomach as a conduit for esophagectomy. In this study, we presented our experience with patients who developed EAC after bariatric surgery and described the challenges encountered and the techniques used. We conducted a retrospective review of our institutional database to identify all patients at our institution who were treated for EAC after previously undergoing bariatric surgery. In total, 19 patients underwent resection with curative intent for EAC after bariatric surgery, including 10 patients who underwent sleeve gastrectomy. The median age at diagnosis of EAC was 63 years; patients who underwent sleeve gastrectomy were younger (median age, 56 years). The median time from bariatric surgery to EAC was 7 years. Most patients had a body mass index (BMI) score of >30kg/m2 at the time of diagnosis of EAC; approximately 40% had class III obesity (BMI score > 40kg/m2). Six patients (32%) had known Barrett's esophagus before undergoing a reflux-increasing bariatric procedure. Sleeve gastrectomy patients underwent esophagectomy with gastric conduit, colonic interposition, or esophagojejunostomy. Only 1 patient had an anastomotic leak (after esophagojejunostomy). Endoscopy should be required both before (for treatment selection) and after all bariatric surgical procedures. Resection of EAC after bariatric surgery requires a highly individualized approach but is safe and feasible.

Multi-modal cell-free DNA genomic and fragmentomic patterns enhance cancer survival and recurrence analysis

The structure of cell-free DNA (cfDNA) is altered in the blood of patients with cancer. From whole-genome sequencing, we retrieve the cfDNA fragment-end composition using a new software (FrEIA [fragment end integrated analysis]), as well as the cfDNA size and tumor fraction in three independent cohorts (n= 925 cancer from >10 types and 321 control samples). At 95% specificity, we detect 72% cancer samples using at least one cfDNA measure, including 64% early-stage cancer (n= 220). cfDNA detection correlates with a shorter overall (p= 0.0086) and recurrence-free (p= 0.017) survival in patients with resectable esophageal adenocarcinoma. Integrating cfDNA measures with machine learning in an independent test set (n= 396 cancer, 90 controls) achieve a detection accuracy of 82% and area under the receiver operating characteristic curve of 0.96. In conclusion, harnessing the biological features of cfDNA can improve, at no extra cost, the diagnostic performance of liquid biopsies.

The impact of refusing esophagectomy for treatment of locally advanced esophageal adenocarcinoma

ObjectivePatients with esophageal cancer may be reluctant to proceed with surgery due to high complication rates. This study aims to compare outcomes between eligible surgical candidates who proceeded with surgery versus those who refused surgery. MethodsCharacteristics and survival of patients with locally advanced (cT3N0M0, cT1-3N+M0) mid-/distal esophageal adenocarcinoma in the National Cancer Database (2006-2019) who either proceeded with or refused surgery after chemoradiotherapy were evaluated with logistic regression, Kaplan–Meier curves, and Cox proportional hazards methods. ResultsOf the 13,594 patients included in the analysis, 595 (4.4%) patients refused esophagectomy. Patients who refused surgery were older, had less distance to travel to their treatment facility, were more likely to have cN0 disease, and were more likely to be treated at a community rather than academic or integrated network program, but did not have significantly different comorbid disease distributions. On multivariable analysis, refusing surgery was independently associated with older age, uninsured, lower income, less distance to a hospital, and treatment in a community program versus an academic/research or integrated network program. Esophagectomy was associated with better survival (5-year survival 40.1% [39.2-41] vs 23.6% [19.9-27.9], P < .001) and was also independently associated with better survival in the Cox model (hazard rate, 0.78 [95% confidence interval, 0.7-0.87], P < .001). ConclusionsThe results of this study can inform selected patients with resectable esophageal adenocarcinoma that their survival will be significantly diminished if surgery is not pursued. Many factors associated with refusing surgery are non-clinical and suggest that access to or support for care could influence patient decisions.

Genome-wide and panel-based cell-free DNA characterization of patients with resectable esophageal adenocarcinoma.

Circulating tumor DNA (ctDNA) holds promise in resectable esophageal adenocarcinoma (EAC) to predict patient outcome but is not yet sensitive enough to be clinically applicable. Our aim was to combine ctDNA mutation data with shallow whole-genome sequencing (sWGS)-derived copy number tumor fraction estimates (ichorCNA) to improve pathological response and survival prediction in EAC. In total, 111 stage II/III EAC patients with baseline (n = 111), post-neoadjuvant chemoradiotherapy (nCRT) (n = 68), and pre-surgery (n = 92) plasma samples were used for ctDNA characterization. sWGS (<5× coverage) was performed on all time-point samples, and copy number aberrations were estimated using ichorCNA. Baseline and pre-surgery samples were sequenced using a custom amplicon panel for mutation detection. Detection of baseline ctDNA was successful in 44.3% of patients by amplicon sequencing and 10.5% by ichorCNA. Combining both, ctDNA could be detected in 50.5% of patients. Baseline ctDNA positivity was related to higher T stage (cT3, 4) (p = 0.017). There was no relationship between pathological response and baseline ctDNA positivity. However, baseline ctDNA metrics (variant allele frequency > 1% or ichorCNA > 3%) were associated with a high risk of disease progression [HR = 2.23 (95% CI 1.22-4.07), p = 0.007]. The non-clearance of a baseline variant or ichorCNA > 3% in pre-surgery samples was related to early progression [HR = 4.58 (95% CI 2.22-9.46), p < 0.001]. Multi-signal analysis improves detection of ctDNA and can be used for prognostication of resectable EAC patients. Future studies should explore the potential of multi-modality sequencing for risk stratification and treatment adaptation based on ctDNA results. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Longitudinal immune monitoring of patients with resectable esophageal adenocarcinoma treated with Neoadjuvant PD-L1 checkpoint inhibition

ABSTRACT The analysis of peripheral blood mononuclear cells (PBMCs) by flow cytometry holds promise as a platform for immune checkpoint inhibition (ICI) biomarker identification. Our aim was to characterize the systemic immune compartment in resectable esophageal adenocarcinoma patients treated with neoadjuvant ICI therapy. In total, 24 patients treated with neoadjuvant chemoradiotherapy (nCRT) and anti-PD-L1 (atezolizumab) from the PERFECT study (NCT03087864) were included and 26 patients from a previously published nCRT cohort. Blood samples were collected at baseline, on-treatment, before and after surgery. Response groups for comparison were defined as pathological complete responders (pCR) or patients with pathological residual disease (non-pCR). Based on multicolor flow cytometry of PBMCs, an immunosuppressive phenotype was observed in the non-pCR group of the PERFECT cohort, characterized by a higher percentage of regulatory T cells (Tregs), intermediate monocytes, and a lower percentage of type-2 conventional dendritic cells. A further increase in activated Tregs was observed in non-pCR patients on-treatment. These findings were not associated with a poor response in the nCRT cohort. At baseline, immunosuppressive cytokines were elevated in the non-pCR group of the PERFECT study. The suppressive subsets correlated at baseline with a Wnt/β-Catenin gene expression signature and on-treatment with epithelial–mesenchymal transition and angiogenesis signatures from tumor biopsies. After surgery monocyte activation (CD40), low CD8+Ki67+ T cell rates, and the enrichment of CD206+ monocytes were related to early recurrence. These findings highlight systemic barriers to effective ICI and the need for optimized treatment regimens.

Abstract CT146: Trifluridine/tipiracil (FTD/TPI) and oxaliplatin as induction chemotherapy (IC) in resectable esophageal and gastroesophageal junction adenocarcinoma (EGAC): Preliminary results from a phase II study

Abstract Background: Pre-operative chemoradiation (CRT) followed by surgery for localized EGAC leads to a pathologic complete response (pCR) rate of 20%. Achievement of pCR is associated with improved overall survival (OS). Therefore, several studies have used IC before CRT to improve pCR rates but saw mixed results. We used a novel combination of FTD/TPI and oxaliplatin as IC before the standard CRT in localized EGAC with the primary objective of increasing the pCR rate. Methods: We enrolled patients (pts) in this open-label, single-arm, multicenter, phase II trial between Jan 2020 and Oct 2022. Pts with potentially resectable EGAC, adequate organ function, ECOG performance status of 0 -1, age &amp;lt;76 years, and endoscopic ultrasound (EUS)-determined node-positive disease with any T-stage or T3-T4a with any N stage were eligible. Pts received three cycles of IC with FTD/TPI (35 mg/m² BID, days 1-5 every 14 days) and oxaliplatin (85 mg/m² every 14 days on day 1). Pts then underwent concurrent CRT (radiation dose of 5040 cGY) with weekly Carboplatin (AUC 2) and Paclitaxel (50 mg/m2) for 6 weeks, followed by surgery. The primary objective was to evaluate the pCR rate. The secondary objectives were 2-year disease-free survival (DFS), 2-year OS, and toxicities. Using a Simon two-stage design, we enrolled 22 evaluable patients in stage 1 with at least 5 pCRs to proceed to stage 2. We collected blood samples at different time points to measure circulating tumor DNA (Ct DNA) as a correlative endpoint. Clinical trial information: NCT04097028. Results: Of the 22 enrolled pts, 19 (86.4%) were male, and 20 (90.9%) were Caucasian. The median age was 61 years, and 12 (54.5%) had a primary disease at the gastroesophageal junction. Twenty (90.9%) pts had T3 disease, and 15 (68.2%) had node-positive disease by EUS. IC led to a 35% or more reduction in SUVmax in 60% of patients before CRT. At the time of data cutoff, 13 (59.1%) had surgery, 1 (4.5%) was awaiting surgery, 5 (22.7%) had progressive disease during the study, and 3 (13.6%) discontinued the study due to adverse events (AEs). Only 2 pts had pCRs, and an additional 4 had near pCRs. Since we could not meet our pre-defined pCR rate in stage 1, the study was closed due to futility. After a median follow-up of 15.8 months, 2-year OS and DFS were 43% and 41%, respectively. Nine (40.9%) had grade 3 or higher AEs. Nausea (59.1%) and fatigue (59.1%) were the most common treatment-related AEs; these were grade 1-2 events. The most common grade 3 or higher events were neutropenia (13.6%) and lymphopenia (9.1%). No febrile neutropenia was noted. Conclusion: IC with FTD/TPI and oxaliplatin before standard CRT failed to improve pCR in resectable EGAC, although it was reasonably well tolerated and showed activity. Ct DNA analysis is ongoing and will hopefully identify a select subgroup of pts who may benefit from this approach. Citation Format: Sarbajit Mukherjee, Sylvia Alarcon, Christos Fountzilas, Sarah Chatley, Renuka Iyer, Deepak Vadehra, Moshim Kukar, Kristopher Attwood, Anthony George, Alyson Brown, Chih-Yi Liao, Hassan Hatoum, Sagila George. Trifluridine/tipiracil (FTD/TPI) and oxaliplatin as induction chemotherapy (IC) in resectable esophageal and gastroesophageal junction adenocarcinoma (EGAC): Preliminary results from a phase II study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr CT146.

Outcome prediction in resectable esophageal adenocarcinoma based on clinical variables, radiomics, and ctDNA.

423 Background: Despite the advent of precision medicine, prediction of survival outcome of esophageal cancer patients remains a challenge. Here we aim to investigate the value of prediction models integrating multi-signal data including radiomics and circulating tumor DNA (ctDNA) data in addition to clinical data for the prediction of resectable esophageal adenocarcinoma (rEAC) related outcomes. Methods: In total n=111 rEAC patients treated with neoadjuvant chemoradiotherapy (nCRT; n=71) +/- anti-PD-L1 (n=40) were included. Baseline clinical variables (n=9) were based on the SOURCE survival prediction model (van den Boorn et al. JNCCN. 2021). The baseline ctDNA data from plasma was derived from fragmentomic and copy number aberrations (ichorCNA) from shallow whole genome sequencing (&lt;5-fold coverage) and a custom next-generation sequencing panel (n=23 genes). Baseline radiomic original features were extracted by the pyradiomics package from CT-image delineated tumor volumes. An initial redundancy filtering was performed to remove correlating variables (r&gt;0.6). We evaluated the predictive performance of baseline ctDNA and radiomics features on overall survival (OS), progression free survival (PFS), and time to progression (TTP), through fitting Cox-regression models. Four ctDNA features were included in the models: P20-150, ichorCNA, fragment end score and mutation detection. For the radiomics features we performed an additional back- and forward variable selection based on Akaike’s Information Criterion. Using the likelihood ratio test we tested if the model fit changed after adding ctDNA and radiomics features to a model with clinical variables. Results: The addition of radiomics to clinical variables improved model fit for OS (p=0.017). Baseline prediction of OS resulted in a C-index of 0.65 using clinical variables only, 0.65 with ctDNA, 0.68 with radiomics and 0.68 with ctDNA and radiomics combined. For PFS model fit improved after adding radiomics (p=0.020) and ctDNA and radiomics combined (p=0.017). Baseline prediction of PFS resulted in a C-index of 0.64 using clinical variables, 0.65 with ctDNA, 0.67 with radiomics, and 0.68 with ctDNA and radiomics combined. For TTP model fit improved after adding radiomics (p=0.008) and radiomics and ctDNA combined (p=0.002). Baseline prediction of TTP resulted in a C-index of 0.64 with clinical variables, 0.65 with ctDNA, 0.71 with radiomics, and 0.72 with ctDNA and radiomics combined. Based on the cox-regression models using clinical variables and radiomics, risk stratification by splitting the cohort in a high and low risk group was possible for OS, PFS and TTP (p&lt;0.001). Conclusions: Combining clinical variables from SOURCE with radiomics data improved predictions of OS, PFS, and TTP among patients with rEAC. Multi-signal integration of clinical and radiomics variables could potentially be used to identify risk groups.

Estrogen-related receptor alpha drives mitochondrial biogenesis and resistance to neoadjuvant chemoradiation in esophageal cancer

Neoadjuvant chemoradiotherapy (nCRT) improves outcomes in resectable esophageal adenocarcinoma (EAC), but acquired resistance precludes long-term efficacy. Here, we delineate these resistance mechanisms. RNA sequencing on matched patient samples obtained pre-and post-neoadjuvant treatment reveal that oxidative phosphorylation was the most upregulated of all biological programs following nCRT. Analysisof patient-derived models confirms that mitochondrial content and oxygen consumption strongly increase in response to nCRT and that ionizing radiation is the causative agent. Bioinformatics identifies estrogen-related receptor alpha (ESRRA) as the transcription factor responsible for reprogramming, andoverexpression and silencing of ESRRA functionally confirm that its downstream metabolic rewiring contributes to resistance. Pharmacological inhibition of ESRRA successfully sensitizes EAC organoids and patient-derived xenografts to radiation. In conclusion, we report a profound metabolic rewiring following chemoradiation and demonstrate that its inhibition resensitizes EAC cells to radiation. These findings hold broader relevance for other cancer types treated with radiation as well.

Current landscape of radiation oncology in esophageal cancer: a narrative review.

Esophageal cancer is an aggressive disease that is the sixth leading cause of cancer-related death worldwide. The overall treatment paradigm for esophageal cancer has changed considerably over the past decade. This narrative review aims to summarize the current landscape of radiation oncology for esophageal cancer. A systematic search of the MEDLINE/PubMed database and Clinicaltrials.gov was performed, focusing on studies published within the last 10 years. Our search queried "esophageal cancer [AND] neoadjuvant radiation" as well as "locally advanced esophageal cancer [AND] definitive radiation". Our search resulted in 298 total references. These were manually reviewed, and only 58 references were within our scope of interest ranging from 2012-2022. For resectable esophageal cancer, neoadjuvant chemoradiation followed by surgery has been defined as the standard of care over the past decade. In patients with incomplete response to neoadjuvant chemoradiation, the benefit of immunotherapy in the adjuvant setting has recently been established. Ongoing studies are examining whether perioperative chemotherapy may be equivalent to neoadjuvant chemoradiation in resectable esophageal adenocarcinoma. For locally advanced esophageal cancer, recent studies have failed to show a benefit with radiation dose escalation in an unselected population, although the use of early positron emission tomography (PET) response to guide dose escalation is currently being studied. Other ongoing studies aiming to improve outcomes in locally advanced esophageal cancer involve using proton beam therapy to reduce toxicity and combining immunotherapy or targeted therapies with chemoradiation to amplify response. Recent advances in radiation oncology may continue to improve outcomes for patients with esophageal cancer.

422. ROBOT-ASSISTED MINIMALLY INVASIVE THORACO-LAPAROSCOPIC ESOPHAGECTOMY VERSUS MINIMALLY INVASIVE ESOPHAGECTOMY FOR RESECTABLE ESOPHAGEAL ADENOCARCINOMA, A RANDOMIZED CONTROLLED TRIAL (ROBOT-2-TRIAL)

Abstract For patients with esophageal adenocarcinoma or cancer of the gastroesophageal junction, radical esophagectomy with 2-field lymphadenectomy is the cornerstone of the multimodality treatment with curative intent. Both conventional minimally invasive esophagectomy (MIE) and robot assisted minimally invasive esophagectomy (RAMIE) were shown to be superior compared to open transthoracic esophagectomy considering postoperative complications. However, no randomized comparison exists between MIE and RAMIE in the Western World for patients with esophageal adenocarcinoma. This is an investigator-initiated and investigator-driven multicenter randomized controlled parallel-group superiority trial. All adult patients (age ≥ 18 and ≤ 90 years) with histologically proven, surgically resectable (cT1-4a, N0–3, M0) esophageal adenocarcinoma of the intrathoracic esophagus or adenocarcinoma of the gastroesophageal junction and with European Clinical Oncology Group performance status 0, 1 or 2 will be assessed for eligibility and included after obtaining informed consent. Patients (n = 218) with resectable esophageal adenocarcinoma of the intrathoracic esophagus or adenocarcinoma of the gastroesophageal junction are randomized to either RAMIE (n = 109) or MIE (n = 109). T. The primary outcome of this study is the total number of resected abdominal and mediastinal lymph nodes specified per lymph node station. Short-term results and the primary endpoint (total number of resected abdominal and mediastinal lymph nodes per lymph node station) will be analyzed and published after discharge of the last randomized patient within this trial. This is the first randomized controlled trial designed to compare RAMIE to MIE as surgical treatment for resectable esophageal adenocarcinoma or adenocarcinoma of the gastroesophageal junction in the Western World. The hypothesis of the proposed study is that RAMIE will result in a higher abdominal and mediastinal lymph node yield specified per station compared to conventional MIE.

186. RECURRENT DISEASE AFTER ESOPHAGEAL CANCER SURGERY; A SUBSTUDY OF THE DUTCH NATIONWIDE IVORY STUDY

Abstract Survival of recurrent esophageal cancer is usually poor, with limited prospects of remission. This study investigated the predictors, patterns and survival of recurrent disease following esophageal cancer surgery. This nationwide cohort study included patients with resectable distal esophageal and gastroesophageal junction adenocarcinoma and squamous cell carcinoma undergoing curatively intended esophagectomy from January 2007 until December 2016 (follow-up until January 2020). Patients with distant metastases detected during surgery were excluded. Univariable and multivariable logistic regression were used to identify predictors of recurrent disease. Multivariable Cox regression was used to determine the association of recurrence site (locoregional or distant) and treatment intent (none, palliative, curative) with post-recurrence survival. Among 4626 patients, 45.1% developed recurrent disease at a median of 11 months postoperatively, of whom most had distant metastases (59.8%). Disease recurrences were most frequently hepatic (26.2%) or pulmonary (25.1%). Young age (≤65 years), male sex, adenocarcinoma, open surgery, transthoracic esophagectomy, non-radical resection, higher T-stage, and (y)pN+ stage were significantly associated with disease recurrence. Overall, median post-recurrence survival was 4 months (95%CI 3.6–4.4). Median survival after locoregional recurrence was 7 months (95%CI 5.7–8.4) and favorable compared to distant recurrence (HR = 0.74, 95%CI 0.65–0.84). For 127 patients that underwent curatively intended treatment for recurrence, median survival was 20 months (95%CI 16.4–23.7). This study provides important prognostic information assisting in the surveillance and counseling of patients after curatively intended esophageal cancer surgery. Nearly half of included patients developed recurrent disease, and risk of recurrence was higher in patients with, amongst others, higher tumor stage, non-radical resection and tumor positive lymph nodes. Overall, patients with recurrent disease had limited prospects of survival, although median survival after curatively intended treatment reached 20 months.

1260TiP The efficacy of the addition of TRAstuzumab and Pertuzumab to neoadjuvant chemoradiation: A randomized multi-center study in resectable HER2 overexpressing adenocarcinoma of the esophagus or gastroesophageal junction (TRAP-2)

Despite promising results following implementation of neoadjuvant chemoradiation (nCRT) prior to surgery in resectable esophageal adenocarcinoma (EAC) (van Hagen et al., NEJM, 2012) and the introduction of adjuvant nivolumab in case of incomplete response (Kelly et al., NEJM, 2021), prognosis remains dismal. Many patients eventually develop metastatic disease, and there is an unmet need to improve current therapies. In 15% to 43% of EAC cases, overexpression and/or gene amplification of the human epidermal growth factor receptor 2 (HER2) is observed.

1249P Older patients experience similar toxicity and survival outcomes to FLOT chemotherapy compared to younger patients

Standard treatment for patients with resectable gastric, gastro-oesophageal junction and oesophageal adenocarcinoma is peri-operative chemotherapy with fluorouracil, oxaliplatin and docetaxel (FLOT). Toxicity is common, particularly fatigue, diarrhoea and neutropaenia. Older patients are perceived to be at higher risk of treatment toxicity and may not be offered standard therapy. We aimed to assess toxicity and survival outcomes for older patients (≥70 years) receiving FLOT at a tertiary centre in the UK.

Apoptosis and autophagy markers predict survival in neoadjuvant treated oesophageal adenocarcinoma patients

BackgroundLess than 20 % of patients with resectable oesophageal adenocarcinoma obtain a pathological response following neoadjuvant chemotherapy. Studies using oesophageal cancer cell lines have shown that drug sensitive tumour cells undergo apoptosis in response to drug treatment, whereas resistant cells induce autophagy and can recover following withdrawal of drug. In this study, we evaluated markers of apoptosis (active/cleaved caspase-3) and autophagy (LC3B) to establish whether these markers are useful prognostic indicators following neoadjuvant therapy.MethodsOesophageal adenocarcinoma tumour tissue from the Northern Ireland Biobank at Queens University Belfast was examined retrospectively. Tumours from 144 patients treated with platinum-based neoadjuvant chemotherapy followed by surgical resection were assembled into tissue microarrays prior to immunohistochemical analysis. Kaplan-Meier survival curves and log-rank tests were used to assess the impact of cleaved caspase-3 and LC3B expression on survival. Cox regression was used to examine association with clinical risk factors.ResultsHigh levels of cleaved caspase-3 were found in 14.6 % of patients and this correlated with a significantly better overall survival (p = 0.03). 38.9 % of patients had high cytoplasmic LC3B expression, which correlated with poor overall survival (p = 0.041). In addition, a distinct globular pattern of LC3B expression was identified in 40.3 % of patients and was also predictive of overall survival (p < 0.001). LC3B globular structures are also associated with tumour recurrence (p = 0.014).When these markers were assessed in combination, it was found that patients who showed low/negative cleaved caspase-3 staining and high/positive staining for both patterns of LC3B had the worst overall survival (p < 0.001). Multi-variate analysis also indicated that this marker combination was an independent predictor of poor prognosis (p = 0.008; HR = 0.046, 95% CI = (0.005-0.443).ConclusionsThe expression of cleaved caspase-3 and specific LC3B staining patterns are associated with overall survival following neoadjuvant treatment. The combination of these markers is an independent indicator of outcome in neoadjuvant chemotherapy treated oesophageal adenocarcinoma.